Sidebar Sidebar
Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

macOS Tahoe 26 on Unsupported Macs Discussion

Status
The first post of this thread is a WikiPost and can be edited by anyone with the appropiate permissions. Your edits will be public.
Because the decision was not based on technical considerations but on commercial ones… it's Apple after all :D

AppleHDA could make a return – just like the compatible for Polaris cards which have been reported working again in beta2
 
  • Like
Reactions: olad and macpro_mid2014
I managed to get my Radeon RX580 back to work in beta 2. I had to disable Whatevergreen during Install. Otherwise the progress bar would get stuck early. Once the install was completed, I enabled it again and rebooted. GPU is working fine now.

Bildschirmfoto 2025-06-24 um 20.48.15.png
 
Last edited:
  • Like
Reactions: macinfo, perez987, amaze1499 and 2 others
hvds said:
MBP11,1 and MBP5,2: success with installing, booting and logging into Tahoe 26b1.
In both cases, using external SSD connected to onboard USB and made clean install. EFIs generated with OCLP 2.4.0 and modified in-place (on target SSD) to use OC 1.0.5 and the respective Info.plist in USB-Map.kext. Thanks again deveedee and others! See post #67.

Also in both cases, needed to first install Sequoia 15.5 from USB installer, and do all the fresh setup (no data migration), and then install 26b1 over it from USB installer. Without first having Sequoia, after clean install of 26b1 I was unable to proceed beyond login as it seemed that system assistant got stuck (3rd picture, from MBP5,2) - maybe it would just have taken longer than the 1hr I waited. Thanks to Larsvonhier for his remark earlier in the Tahoe posts.

So far so good or even excellent for this 1st beta - didn't expect more at this point.
Click to expand...
MBP11,1: updated to 26.0b2 from b1.
On external SSD, using USB installer made from InstallAssistant.pkg downloaded via Mr.Macintosh. Installed over b1 which was installed over clean installation of 15.5 (direct clean Tahoe did not get beyond login/password entry).
Using same OCLP EFI as before, i.e. a modified 2.4.0.
Running at usable speed after letting it calm down for >1hr, until the Dock appeared at all. No patches applied. Writing this post from Safari on this Tahoe system.
Thunderbolt Ethernet working.
Sound not working.
At this early state of Tahoe, that means happiness...

Edit:
similarly, MBP5,2 updated to 26.0b2.
The dual-USB3 expresscard (nanotech) that I use to connect external keyboard and mouse still works in Tahoe.
Didn't get Safari to work yet.
 

Attachments

  • Bildschirmfoto 2025-06-24 um 20.13.22.png
    Bildschirmfoto 2025-06-24 um 20.13.22.png
    42.1 KB · Views: 48
  • Bildschirmfoto 2025-06-24 um 20.42.51.png
    Bildschirmfoto 2025-06-24 um 20.42.51.png
    21.9 KB · Views: 43
  • Bildschirmfoto 2025-06-25 um 08.50.53.png
    Bildschirmfoto 2025-06-25 um 08.50.53.png
    44.9 KB · Views: 38
Last edited:
  • Like
  • Love
Reactions: JoinMeinHeaven, macinfo, ronton3 and 3 others
dosdude1 said:
OCLP is not going anywhere anytime soon, regardless of if Mykola is able to work on the project or not. There are many other developers working on the project as well, who will continue development on it throughout the lifecycle of Tahoe. Now, of course next year when Apple completely drops support for Intel, that’s it... No more binaries compiled for Intel, and there’s nothing anybody can do about that. So only at that point is when development and work on OCLP will stop. So, everyone can rest assured that every effort will continue being made to achieve as much legacy system compatibility with Tahoe as possible.
Click to expand...
Thanks @dosdude1 for the hopeful message.
 
  • Like
Reactions: JoinMeinHeaven, macinfo and hvds
deeveedee said:
I got myself into a little mess with FileVault enabled in Tahoe Beta 2 on my HackMini8,1. FileVault would not accept my password. I booted into Tahoe Beta Recovery, but was unable to unlock and decrypt through "normal" mechanisms. I was able unlock and decrypt by booting into Tahoe Recovery as follows:
  1. Boot Tahoe Beta 2 Recovery
  2. Select Tahoe Beta Volume to recover
  3. Open Utilities > Terminal
  4. execute 'diskutil apfs listUsers [Tahoe Beta Volume] to view user UUIDs and note the UUID for 'Local Open Directory User' (where Tahoe Beta Volume is /dev/diskXsY)
  5. execute 'diskutil apfs decryptVolume [Tahoe Beta Volume] -user [UUID noted in step 4]
  6. when prompted for password, enter your user password for your Tahoe Beta Volume
The encrypted volume should start to decrypt. Monitor decryption progress with 'diskutil apfs list'

After decryption is complete ('diskutil apfs list' reports FileVault 'No' for your Tahoe Beta Volume), reboot. You should now be able to boot and login to your Tahoe Beta Volume without FileVault.
Click to expand...
Thanks @deeveedee it also solved my FileVault problem I mentioned in the Sequoia thread.
Using your steps, I could decrypt both of my MBP11,2 volumes.
 
  • Like
Reactions: MacRumors3590, sinbad21, deeveedee and 2 others
Does anyone have any ideas on how to restore the large, central brightness
and volume control display in the Tahoe?

I don't like the fact that the volume and brightness display
now appears in the top right corner.
 
Has anyone successfully run Tahoe beta 2 in Parallels VM on MBA 2016 running Sequoia 15.6 using OCLP?
 
Last Tuesday, I installed macOS 26 Tahoe @OCLP 2.4.0 on my 18.3 iMac.
It took a little longer than with other supported macOS versions, but Tahoe was finally ready to boot.

iMac18.3 @macOS 26-01.pngiMac18.3 @macOS 26-02.png
A quick check of the system settings showed that Bluetooth was fully functional, but there was no network. The lack of Wi-Fi was to be expected, but the fact that LAN didn't offer anything either was surprising.
So I opened the OCLP app to perform the post-install and experienced the next surprise:
OCLP 2.4.0 Post-Install Menu.png
A little online research did yield the Kernel_Debug_Kit_26.0_build_25A5279m.dmg ...

Kernel_Debug_Kit_26.0_build_25A5279m.png
..., but how to integrate it to OC 2.4.0 is a bit beyond my capabilities.

What would I need to do to at least establish LAN?

iMac18.3 @macOS 26-LAN.png
Also Audio doesn't work.

iMac18.3 @macOS 26-Audio.png


Related suggestions are welcome. :)
 
Last edited:
  • Like
Reactions: amaze1499, ronton3 and deeveedee
LuckyOldMan said:
Last Tuesday, I installed macOS 26 Tahoe @OCLP 2.4.0 on my 18.3 iMac.
It took a little longer than with other supported macOS versions, but Tahoe was finally ready to boot.

View attachment 2523358View attachment 2523359
A quick check of the system settings showed that Bluetooth was fully functional, but there was no network. The lack of Wi-Fi was to be expected, but the fact that LAN didn't offer anything either was surprising.
So I opened the OCLP app to perform the post-install and experienced the next surprise:
View attachment 2523364
A little online research did yield the Kernel_Debug_Kit_26.0_build_25A5279m.dmg ...

View attachment 2523367
..., but how to integrate it to OC 2.4.0 is a bit beyond my capabilities.

What would I need to do to at least establish LAN?

View attachment 2523370
Also Audio doesn't work.

View attachment 2523371


Related suggestions are welcome. :)
Click to expand...
Can you send your config.plist? I'll try to turn on the wi-fi.
 
  • Like
Reactions: ronton3 and LuckyOldMan
LuckyOldMan said:
A little online research did yield the Kernel_Debug_Kit_26.0_build_25A5279m.dmg ...

..., but how to integrate it to OC 2.4.0 is a bit beyond my capabilities.
Click to expand...
The appropriate KDK is pulled automatically by OCLP if OCLP supports the current macOS to be patched (contingent upon the KDK's availability from Apple). See here for my modified OCLP results where I simply changed OCLP's macOS constants for Tahoe compatibility.

To properly patch Tahoe, we'll need an OCLP modified for new frameworks in Tahoe.
 
  • Like
Reactions: macpro_mid2014, olad, ronton3 and 1 other person
deeveedee said:
The appropriate KDK is pulled automatically by OCLP
Click to expand...
I know that, but I remember a very similar situation when OCLP didn't download the correct KDK (some version of Sonoma?), but one was able to manually install it with the correct KDK.
I was hoping for a similar effect, but I don't remember how I did it back then.
 
I managed to get through the welcome from a clean install to a clean disk of the beta 2 system. Yes, it's true, the sound was removed. This is bad!
t.png
 
idenis42 said:
Try this first. Let me know how you are doing in the PCI tab.
Click to expand...
I did get some changes - of course. ;)

First pic ist config.plist-standard - second after your modification.

iMac18.3 @macOS 26-PCI-standard.pngiMac18.3 @macOS 26-PCI-mod.png
Quite a difference, but still no WLAN to activate for connnection.

iMac18.3 @macOS 26-WLAN.png
 
Last edited:
LuckyOldMan said:
I know that, but I remember a very similar situation when OCLP didn't download the correct KDK (some version of Sonoma?), but one was able to manually install it with the correct KDK.
I was hoping for a similar effect, but I don't remember how I did it back then.
Click to expand...
OCLP needs an active network connection to retrieve the KDK. If no network connection is available, then KDK would need to be manually installed.
 
  • Like
Reactions: LuckyOldMan
The changes were dramatic—as if I hadn't patched an OCLP-supported macOS yet.
The boot process was more or less normal shortly before logging in—after logging in, there was no more graphics support/a white desktop, ...

WLAN-iMac18.3-01.jpg

... a different resolution (also on the OC-picker), and opening the Control Panel seemed like slow motion.

WLAN-iMac18.3-02.jpg

The Wi-Fi is enabled—the logo is shown in the top right.

Before I can even search for the network, the iMac freezes.
I've now switched to the iMac 18.2, hoping the freeze won't last too long. But it doesn't look good—it's probably a permanent freeze.
I tried several times - always the same, even on macOS Sequoia where WLAN was also missing.
 
LuckyOldMan said:
The changes were dramatic—as if I hadn't patched an OCLP-supported macOS yet.
The boot process was more or less normal shortly before logging in—after logging in, there was no more graphics support/a white desktop, ...

View attachment 2523452

... a different resolution (also on the OC-picker), and opening the Control Panel seemed like slow motion.

View attachment 2523453

The Wi-Fi is enabled—the logo is shown in the top right.

Before I can even search for the network, the iMac freezes.
I've now switched to the iMac 18.2, hoping the freeze won't last too long. But it doesn't look good—it's probably a permanent freeze.
I tried several times - always the same, even on macOS Sequoia where WLAN was also missing.
Click to expand...
This is how it should be so that I know exactly where the joints are. Now try this one.
 

Attachments

  • config.plist.zip
    8.8 KB · Views: 26
  • Like
Reactions: LuckyOldMan
You must log in or register to reply here.
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.
Top Bottom
Back